Improvement in bolts



, UNrrnn STATES ArnNr einen.

WILLIAM J. CLARK, OF SOUTHINGTON, CONNECTICUT.

IMPROVEMENT IN BOLTS.

Specification forming part of Letters Patent No. 410,327, dated October20, 1863.

To all whom, it may concern:

Beit known that I, WM. J. CLARK, of Southin gton, Hartford county, andState of Connecticut, have invented certain new and useful Improvementsin Bolts, ofwhich the following is a full, clear, and accuratedescription, reference being had to the accompanying drawings, whichmake part of this specification, and in which- Figure l represents alongitudinal elevation of my bolt; Fig. 2, a longitudinal view showingthree of its corners. Fig. 3 shows a crosssection of Fig. l at .r x andthe head of the bolt. Fig. 4 is acrosssection at x of Fig. 2, and thehead of the bolt.

In bolts heretofore made with long square lshanks, from round iron, ithas been found impossible to make the corners of the long square portionof the bolt sufficiently sharp and extended to fill fully the corners ofa square mortise large enough to permit the passage of the screw andround portion ofthe bolt, and thus to prevent the bolt from turning inthe mortise. It is therefore the object of my invention to remedy thisdefect by making from round iron a bolt having a square shank of anydesired length, so that it shall not turn in a square mortise that shalladmit the screw-thread and round portion of the bolt to pass through it.

To enable others to make and use my invention, I will proceed todescribe its construction and operation.

Fig. l of the drawings shows the general form of my bolt when linished,and as viewed 011 one of its sides. Introducing into the machine ared-hot rod of round iron, it is clamped by dies, and so much of thelength of the bolt as may be required to be square is compressed intothe form shown by the drawings, while at the same time the dies form ananvil, against which the head is formed by another, die as described inan application for a patent I now have pending before the Patent Office.

To raise or force out the corners of the bolt to thefullness ordimensions desired, the compressing or swaging dies must be of such formas to force a portion of the metal of the body of the rod from thecenter to the corners of the square. This may be effected by the dieshaving convex faces on each of their four compressing surfaces, or theymay carry a rib,

bead, or angular projection on their faces longitudinally, or ribs,beads, or angular projections on any or all their swaging-surfaces,instead of being convex, as above described, for it is indifferent to myinvention what the form of the dies, so that the desired result is thusproduced.

In Fig. 3 the sides of the square portion of the bolt are showndepressed into the form of a regular curve on each face from the raisedcorners, or, in other words, the section shows the sides of the squareto be concave, while in Fig. 4 the corners are shown projecting beyondthe diameter ofthe round part of the bolt.

Fig. 4 shows the appearance of the bolt as cut transversely at the linex x in Fig. 2, the circle c showing the diameter of the bolt at the linex a, while the corners b, b', b2, and b3 show the projections of thecorners at the line x x of Fig. l, and the outer circle, c, of Figs-3and 4, shows the circular head of the bolt, as seen longitudinally f'romwhere the bolt is cut in Fig. 2.

It is obvious tha-t the head may be made square or of any other shape aswell as round, for I do not mean to confine myself to any particularshape for the head of the bolt.

Fig. 2 shows two of the sides andthree corners of the bolt as if ofatruesquare; but the corners are forced up fully in the manner abovedescribed. l

I do not claim in this application the forniing of a short square shankby upsetting` 7 a portion of the round rod from which the bolt is to bemade, nor do I claim, broadly, swaging a portion of the shank of a boltmade of round iron into a square form merely, for neit-lier of these arenew 5 but Wha-t .I do claim as of my invention, and desire to havesecured by these Letters Patent, is-

The bolt substantially herein described, constitutin g a new article ofmanufacture, as herein set forth.

In testimony whereof I have hereunto subscribed my name.

WM. J. CLARK.

Witnesses HENRY BALDWIN, A. BROOKE JoNns.

